Intra-tumoral IgG recognize Neu5Gc-glycans. (a) Tumors were harvested from vaccine or control immunized mice (NGpos or NGneg, respectively), minced and then IgG antibodies were purified with Protein-A. 20 ng/μl of intra-tumoral purified IgG antibodies were analyzed on sialoglycan microarrays, then detected by Cy3-anti-mouse IgG. Results are presented as heat map of IgG reactivity in relative fluorescent units (RFU), per glycan per mouse, against the collection of Neu5Gc-glycans or Neu5Ac-glycans (Blue-white-red scale represent 0-50-100 percentiles). (b) Average IgG response of individual mice against Neu5Gc-glycan or Neu5Ac-glycans on microarray (Two-Way ANOVA with Bonferroni posttests, ** p<0.01).